You can use the Windows USB/DVD Download Toolfrom codeplex to extract the ISO on a USB pen (must be 4GB+), avoiding to waste a DVD. After the USB Tool finished creating the boot drive, restart your computer: note that it is VERY IMPORTANT. DO NOT SIMPLY RUN SETUP SINCE IT WILL OVERWRITE YOUR CURRENT OS but to restart and boot into the USB drive. Then you will be given the regular Windows installer window. (see also here for more details)

Note that sometime a new release could introduce some undesired problem, especially if you are a programmer: for example it seems that the March pre-release 10044 introduced some problems in debugging with Visual Studio (and perhaps that it is why in the MSDN there is still the 9926 pre-release). Then you can possibly configure your PC to have a dual boot. To properly install that preview on a new partition in the HD of your Windows 8.1 PC you can follow one or more of the following links: link1, link2, link3, link4

Enable dual boot in Control Panel\System and Security\System\Advanced system settings

The OS preview Build 9926 takes about 23 GB of disk space, so you need to install it in a partition of at least 30GB … even thought I suggest to have a bigger one (let’s say more than 100GB if you have enough space on your disk) if you think to make some development: you can always easily shrink that volume in a second phase if you want, while extending it could be more complex and time consuming if there is not contiguous unallocated space (in that case, the Extend volume… right mouse option is disabled and you need to use some external tool like AOMEI Partition Assistant [even the free Standard Edition].

As Gabe Aul wrote, based on Windows Insider feedback, Microsoft is going to send out builds more frequently to Windows Insiders that have selected “Fast” preview builds. That means you can getting fresher code with all of the features and fixes, more often – but builds may include more bugs. Read his blog for more details. To switch to slow or fast builds on your PC, go to Settings>Update & recovery>Advanced options. On your phone, go instead to the Windows Insider app.

Slow or Fast build selection

Other good suggestions from Gave are:

Go to the Insider Hub in the Start menu on your PC for the latest updates, including new features (like the new Office preview apps) and simple workarounds to issues you may encounter with the new builds. (A Hub for phones is coming soon.)

Check out the new Get Started app (also in the Start menu) that guides you through the latest features.

For developers: the Windows 10 developer tools are now available and provide an early look at the tools and features that are coming with the Windows universal app platform. See how your apps can take advantage of new Windows capabilities and social integration to create experiences that delight your customers, whether they’re running on a phone, tablet, or PC. Application developers can get Insider access to Visual Studio 2015 CTP6 and the tools, includingSDK,here. Hardware developers can get access to tools here. (English-language availability only). See also:
– Windows 10 Technical Preview universal app samples.
–Steps to install Windows 10 development tools for Visual Studio 2015 RC

For IT pros: Have questions about drivers, virtualization, and multi-boot scenarios? Ready to try the in-place upgrade process? Need help with a specific setup or installation problem? Check out these TechNet resources:

With Windows 10 Insider Preview Build 10074, developers cannot enable Developer Modein the Settings app for installing and testing apps on this build. We’ll enable this in an upcoming build. In the meantime, you will need enable your device for development using the Group Policy Editor (use of gpedit to enable your device):

Allows development of Windows Store apps and installing them from an integrated development environment (IDE) (Enables your device for development from Visual Studio)

Reboot your machine.

In next releases, the “For developers” section will be used for setting that features …

Local Group Policy Editor

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Update for Windows preview build 10074 and VS 2015 RC

As stated here, if you are using a different development environment than Visual Studio 2015, you can download a standalone Windows 10 SDK installer BUT you don’t need to do it if you’re using Visual Studio 2015 – it already includes the SDK. However, if the emulators are not working properly, an alternative solution suggested in the MS Developer forum, is to install the Windows Emulators separately (https://dev.windows.com/downloads/windows-10-developer-tools ): scroll to the bottom of the page and install the and Windows 10 emulators outside of Visual Studio setup). BECAREFUL: I tried to install also the Windows 10 SDK but, after doing that all the Visual Studio environment broke (even a new blank solution didn’t compile anymore because something was missing) … so I had to reinstall all the Visual Studio environment!!

The xml file defining the UAP of our platform is in C:\Program Files (x86)\Windows Kits\10\Platforms\UAP and the available extension that can be referenced in our project are in C:\Program Files (x86)\Windows Kits\10\Extension SDKs .

Hi Moreno! That is the other alternative but if you want to develop something for the new Windows 10 platform, using Visual Studio 2015 CTP new specific features, I think it is better to use a dual boot for performance reasons (running the SO in a Virtual Machine adds a further layer that slow down further more the already slow performance of a preview).
I should also say that till now I didn’t find that Preview to much instable anyway 🙂

I let you Know in the next days … waiting for next “more final” preview!
😉